#include using namespace std; using ll = long long; using ld = long double; template using V = vector; using VI = V; using VL = V; using VS = V; template using PQ = priority_queue, greater>; using graph = V; template using w_graph = V>>; #define FOR(i,a,n) for(int i=(a);i<(n);++i) #define eFOR(i,a,n) for(int i=(a);i<=(n);++i) #define rFOR(i,a,n) for(int i=(n)-1;i>=(a);--i) #define erFOR(i,a,n) for(int i=(n);i>=(a);--i) #define all(a) a.begin(),a.end() #define rall(a) a.rbegin(),a.rend() #define out(y,x) ((y)<0||h<=(y)||(x)<0||w<=(x)) #ifdef _DEBUG #define line cout << "-----------------------------\n" #define stop system("pause") #endif constexpr ll INF = 1000000000; constexpr ll LLINF = 1LL << 60; constexpr ll mod = 1000000007; constexpr ll MOD = 998244353; constexpr ld eps = 1e-10; templateinline bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; }return false; } templateinline bool chmin(T& a, const T& b) { if (a > b) { a = b; return true; }return false; } inline void init() { cin.tie(nullptr); cout.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } templateinline istream& operator>>(istream& is, V& v) { for (auto& a : v)is >> a; return is; } templateinline istream& operator>>(istream& is, pair& p) { is >> p.first >> p.second; return is; } templateinline V vec(size_t a) { return V(a); } templateinline V defvec(T def, size_t a) { return V(a, def); } templateinline auto vec(size_t a, Ts... ts) { return V(ts...))>(a, vec(ts...)); } templateinline auto defvec(T def, size_t a, Ts... ts) { return V(def, ts...))>(a, defvec(def, ts...)); } templateinline void print(const T& a) { cout << a << "\n"; } templateinline void print(const T& a, const Ts&... ts) { cout << a << " "; print(ts...); } templateinline void print(const V& v) { for (int i = 0; i < v.size(); ++i)cout << v[i] << (i == v.size() - 1 ? "\n" : " "); } templateinline void print(const V>& v) { for (auto& a : v)print(a); } templateinline T sum(const V& a, int l, int r) { return a[r] - (l == 0 ? 0 : a[l - 1]); } templateinline void END(T s) { print(s); exit(0); } void END() { exit(0); } class unionfind { VI par, rank; int forest_num; public: unionfind(const int& n) : par(n), rank(n, 1), forest_num(n) { FOR(i, 0, n)par[i] = i; } int root(int x) { if (par[x] == x)return x; return par[x] = root(par[x]); } int size(int x) { if (par[x] == x)return rank[x]; return size(par[x]); } void unite(int x, int y) { int rx = root(x), ry = root(y); if (rx == ry)return; if (rank[rx] < rank[ry]) { par[rx] = ry; rank[ry] += rank[rx]; } else { par[ry] = rx; rank[rx] += rank[ry]; } --forest_num; } bool same(int x, int y) { return root(x) == root(y); } int fnum() { return forest_num; } }; int main() { init(); int n, m, k; cin >> n >> m >> k; w_graph g(n); FOR(i, 0, m) { int a, b, c; cin >> a >> b >> c; --a, --b; g[a].emplace_back(b, c); g[b].emplace_back(a, c); } { VI dp(n, INF); dp[0] = 0; queue bfs; bfs.push(0); while (!bfs.empty()) { int cur = bfs.front(); bfs.pop(); for (auto [to, c] : g[cur]) { if (!chmin(dp[to], dp[cur] + 1))continue; bfs.push(to); } } if (dp[n - 1] < k)END(0); } auto check = [&](int x)->bool { VI dp(n, INF); dp[0] = 0; queue bfs; bfs.push(0); while (!bfs.empty()) { int cur = bfs.front(); bfs.pop(); for (auto [to, c] : g[cur]) { if (!chmin(dp[to], dp[cur] + (c > x)))continue; bfs.push(to); } } return dp[n - 1] < k; }; int ng = 0, ok = 500000; while (ok - ng > 1) { int mid = ok + ng >> 1; if (check(mid))ok = mid; else ng = mid; } print(ok); return 0; }